1. Field of the Invention
The invention relates to methods for treating mixtures of alkyl substituted phenols so that they will not cause discoloration when used as peroxide inhibitors in polyols and more particularly relates to methods of treating mixtures of alkyl substituted phenols by means of the addition of trioxane.
2. Prior Art
Many decolorizing agents now in use remove color by physical adsorption. The most common materials to remove color by this means are represented by charcoals, blacks (such as carbon black), clays and earths. Other compounds remove color by chemical reaction and are frequently more specific as to the materials they can remove color from than the physical adsorption agents. While attempts have been made to predict compound colors, such as by electronegative or steric contributions of substituents to aromatic rings, numerous exceptions to rules relating color to structure require color prediction to be based largely on empirical observations.* As a result, attempts to remove color from a specific compound tend to be strictly trial and error operations. *Griffiths, John. Colour and Constitution of Organic Molecules. London: Academic Press (1976), pp. 89-90.
With regard to the instant invention, a problem arose in finding a substitute for 2,6-di-t-butyl-paracresol which is used as a peroxide inhibitor in commercial polyol formulations. As the supplies of the paracresol became short, other compounds were tried as inhibitors. It was found that di-t-butyl nonylphenol would give the desired peroxide inhibiting effect and would help prevent scorching of the resultant foam made from the polyol formulation. However, it was discovered that this inhibitor would cause undesirable discoloration of the polyol and the subsequent foam. It is therefore an object of this invention to find an agent which will remove the color from the nonylphenol inhibitor.